title: Impact of peripheral levels of chemokines, BDNF and oxidative markers on cognition in individuals with schizophrenia.
abstract: OBJECTIVE
  To investigate possible differences in peripheral levels of chemokines, BDNF and oxidative markers between patients with Schizophrenia (SZ) and matched healthy controls, and investigate the correlation of these biomarkers with cognitive performance.
  
  
  METHODS
  Thirty individuals with SZ and 27 healthy controls were included and the following plasmatic biomarkers' levels were determined according to manufacturers' instructions: BDNF, TBARS, protein carbonyl content (PCC) and the chemokines CXCL-10/IP-10, CXCL-8/IL-8, CCL-11, CCL-24/Eotaxin-2, CCL-2/MCP-1, CCL-3/MIP-1. Selected neuropsychological tasks were administered to assess verbal learning (Hopkins Verbal Learning Test), verbal fluency (FAS test), working memory (Visual Working Memory Task, Keep Track Task, Letter Memory Task), set shifting (Plus-minus task, Number-letter task), inhibition (Computerized Stroop Task, Semantic Generation Task) and complex executive function tasks (Tower of London and the shortened version of the WCST-64).
  
  
  RESULTS
  Compared with the healthy control group, individuals with SZ presented significantly higher levels of BDNF and the chemokine CCL-11, and lower levels of TBARS and the chemokine CXCL-10/IP-10. When we examined only the SZ group, BDNF levels were positively correlated with semantic generation tasks. Working memory ability was negatively correlated with PCC. Regarding chemokines, CCL-11 was negatively correlated to performance in working memory test, and positively correlated with cognitive flexibility task. CXCL-8/IL-8 was positively correlated with verbal fluency. CCL-24/Eotaxin-2 was positively correlated with semantic generation ability and letter memory task.
  
  
  CONCLUSIONS
  Our results indicate that cognitive performance in SZ is associated with mediators of neuroplasticity that can be measured peripherally.
authors.affiliation: Schizophrenia Program (PROESQ), Department of Psychiatry, Universidade Federal de São Paulo, Rua Machado Bittencourt, 222, São Paulo, SP CEP 04044-000, Brazil. elsonmed@gmail.com
authors.forename: Elson
authors.initials: E
authors.lastname: Asevedo
authors.forename: Ary
authors.initials: A
authors.lastname: Gadelha
authors.forename: Cristiano
authors.initials: C
authors.lastname: Noto
authors.forename: Rodrigo B
authors.initials: RB
authors.lastname: Mansur
authors.forename: André
authors.initials: A
authors.lastname: Zugman
authors.forename: Síntia I N
authors.initials: SI
authors.lastname: Belangero
authors.forename: Arthur A
authors.initials: AA
authors.lastname: Berberian
authors.forename: Bruno S
authors.initials: BS
authors.lastname: Scarpato
authors.forename: Emilie
authors.initials: E
authors.lastname: Leclerc
authors.forename: Antônio L
authors.initials: AL
authors.lastname: Teixeira
authors.forename: Clarissa S
authors.initials: CS
authors.lastname: Gama
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Bressan
authors.forename: Elisa
authors.initials: E
authors.lastname: Brietzke
mesh_terms: D000328:Adult; D001288:Attention; D019208:Brain-Derived Neurotrophic Factor / Q000097:blood*; D016022:Case-Control Studies; D018925:Chemokines / Q000097:blood*; D003072:Cognition Disorders / Q000209:etiology*; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D050050:Protein Carbonylation / Q000502:physiology; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000097:blood* / Q000150:complications*; D012565:Schizophrenic Psychology; D018709:Statistics, Nonparametric; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism*; D014706:Verbal Learning
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D018925:Chemokines; D017392:Thiobarbituric Acid Reactive Substances
keywords: BDNF; Biomarkers; Chemokines; Cognition; Oxidative stress; Schizophrenia